1. Field of the Invention
This invention relates to scavenging oxygen and particularly, although not exclusively, relates to scavenging oxygen in an assembly which contains a relatively dry and/or water free packaged material.
2. Description of Related Art
WO2008/090354 describes a beverage container including a shell made from a polymer and incorporating a catalyst, for example a palladium catalyst. A closure of the container incorporates a plug which includes a source of hydrogen, for example a hydride. In use, with a beverage in the container and the closure in position, the headspace in the container will be saturated with water vapour due to evaporation of water from the beverage. The vapour contacts the hydride associated with the plug and as a result the hydride produces molecular hydrogen which migrates into the polymer matrix of the shell and combines with oxygen which may have entered the container through its permeable walls. A reaction between the hydrogen and oxygen takes place, catalysed by the catalyst, and water is produced. Thus, oxygen ingressing the container is scavenged and the contents of the container are protected from oxidation.
The generation of the oxygen in the embodiments of WO2008/090354 is dependent on there being a water-containing material, for example beverage, within the container which can generate a water vapour pressure sufficient to trigger the production of hydrogen from the hydride. However, some dry materials are sensitive to oxygen and it is therefore desirable to package such oxygen-sensitive dry materials in low oxygen atmospheres and/or in packages where oxygen is scavenged, thereby to extend the shelf life of such dry materials.
It is an object of the present invention to address the above described problem.